Professor Derek Yellon, The Hatter Cardiovascular Institute, University College London, UK and colleagues studied 57 patients undergoing elective coronary artery bypass graft surgery. Of these, 27 received remote ischaemic preconditioning, namely three five-minute cycles of having the blood flow in one arm restricted using an automated cuff-inflator, with a five-minute periods between each cycle where the cuff was deflated.

The other 30 patients acted as a control group. All patients had the amounts of troponin T in their blood measured before surgery and at 6, 12, 24, 48 and 72 hours after surgery. Troponin T is a cardiac protein which can be released into the bloodstream following the “injury” to the heart during surgery, and release of such proteins is associated with poor short- and long-term clinical outcomes after surgery.

The researchers found the total troponin T released 72 hours after surgery was reduced from 36.12 µg/l in the control group to 20.58 µg/l in the remote ischaemic preconditioning group, a reduction of 43 percent.